I recently had the opportunity to do a mock-up at home. I was comparing the new Soraa MR-16 LED lamp with my existing halogen MR-16 lamps. Soraa was one of my favorite new products at last year's LightFair, and they continue to impress me. You can easily see how clean the beam is by comparing the two photos above. Less evident from the photo is the fact that the Soraa LED renders the wall more like daylight does. These lamps also have a little backlight, so while admittedly not as nice as with the halogen lamps, the glass fixtures where they are installed do glow a little.
I have been reluctant to hop on the LED bandwagon, but my recent experiences have been good ones. We are not all the way there yet, but I think we are getting warmer! The important thing is for lighting manufacturers (and legislators) to focus on lighting quality and not just lighting quantity.
I was recently in one of those big box home stores helping my parents shop for things for the new house they are building. We looked at lights and ceiling fans. We checked out some electrical devices, outlets, and switches. We looked at carbon monoxide and smoke detectors - hard wired or battery powered? Dual technology or separate? We checked out some appliances. We walked all the way around the store looking for a public restroom... My point is that we were there for a while - 30 minutes or maybe an hour - when I noticed that someone in the lamp (light bulb) aisle was standing in the same place staring at the same lamps when arrived AND when we left.
It used to be so easy. The only question you had to answer when replacing a light bulb (lamp) was, "How many Watts?" But that was then. I'm here to save you a few minutes in the lamp aisle at the home store. Before your next trip, be armed with the answers to the following five questions:
1. How Bright?
Today we have to think in Lumens instead of Watts. An old 100 watt lamp produced about 1600 lumens. A 60 watt standard incandescent lamp is about 800 lumens, and 40 watt incandescent = about 450 lumens. Before you shop, know how bright you need the light to be - in lumens.
2. What Color?
Not all "white" light is the same color. For more on that topic, check out the pictures in this previous post. The point is that most of today's sources are available in different color temperatures. To most closely resemble incandescent light, select a warm hue, between 2500 and 2800 Kelvin.
3. Where Used?
This question really embodies lots of other questions. Is it in an enclosed fixture? Indoors or outside? In a transient space like a closet? Somewhere extremely hot or cold? Is it used to accent a piece of art, or does it need to be fairly shadow-free? Certain CFLs don't do well in winter temperatures, LEDs prefer the cold. Most LEDs aren't designed for fully enclosed fixtures. Many CFLs aren't either. CFLs generally take a little time to get fully bright, so they might not be the best choice for closets. LEDs tend to be very directional and better for accent lighting, but can be diffused for general lighting. CFLs are great for general shadowless illumination but are never very directional. Know where the new lamp will be used.
4. How Controlled?
Is the lamp you are replacing on a switch or a dimmer? If it is controlled with a dimmer, replacement options are more limited, and you should check dimmer compatibility before you purchase a replacement.
5. How Much Money?
Consider both initial cost and ongoing costs. To spend the least money today, buy an incandescent or halogen replacement lamp. In the long run, this choice will cost the most in energy and replacement lamps, even though the initial outlay is the smallest for this category. The middle of the road option is fluorescent. It will cost a little more today, but will last a little longer and save a little more energy than the traditional sources. Top of the line is LED. These still cost the most, but will provide the most light per watt and will last the longest...provided you buy a quality product and use it in an appropriate application.
If you head to your local light bulb store with the answers to these questions in mind, you should save yourself a few minutes. Maybe you'll even have enough time to browse the clearance aisle and get one of those inflatable snow globes at 75% off!
Incandescent Replacement Lamps
There are three viable major categories of incandescent lamp replacements available today. Think of it like an election.
Consider all of the options and then make your selection - cast your vote. Sometimes, like in an election, you may have to pick the best of the worst...but you do have a choice, so your duty is to become informed about those options before making your selection.
This lamp type is most similar to incandescent in cost, color, physical appearance, light, dimming behavior,
technology...in nearly every way. Halogen is about 30% more efﬁcient than standard incandescent and lasts about
twice as long. The advantages and disadvantages almost perfectly align with advantages and disadvantages of incandescent lamps. They provide instant-on light. They are fully dimmable, The color rendering (CRI) is 100. With
incandescent or halogen, there are no color temperature options They do not require a ballast. They are mercury free,
TCLP and RoHS compliant. They are not sensitive to ambient temperature. They tend to be sensitive to vibration..
They produce heat when they operate. An A-lamp replacement will cost under $2 and will pay you back $3.08 in energy savings over its lifetime.
This lamp type is the one consumers are being told to use instead of incandescent. CFL is about 75% more efﬁcient
than incandescent and lasts about ten times as long. Their function is actually quite different than incandescent, but
they have been fairly common for ﬁfteen years now, so people have grown accustomed to their strengths and weaknesses. They aren’t exactly “instant-on”, but require a brief warm-up, so they are not the best option for very transient spaces or spaces controlled by occupancy sensors. They can be partially dimmable with the proper ballast, The color rendering (CRI) can be low - and that is one reason the CFL has gotten a bad reputation, but look for a CFL lamp with a CRI in the mid-80s for satisfactory color rendering.
Often I hear people say, “I just hate the color of ﬂuorescent light.” Fortunately, ﬂuorescent is available in a variety of colors. Be aware of that and be sure to get a color that you DO like. Once upon a time, lamps available in big box stores did not display the information needed to select the color. But now that is changing. Starting in 2011, the Federal Trade
Commission began requiring lamp packaging to bear a label like this:
Notice the section called "Light Appearance" which indicates how warm or cool the light looks. The warm colors more closely resemble incandescent.
This will be an even more useful tool when CRI is included, shown as “Color Accuracy” in the above DOE Lighting Facts label for LED. CFL lamps do require a ballast. They are not mercury free, but the small amount of mercury used in a high quality lamp can make it TCLP and RoHS compliant. They are sensitive to ambient temperature, and don’t operate as well in cold weather. However, there are lamp ballast combinations available that work well in temperatures down to -10 degrees F. Compared to incandescents, they are not particularly sensitive to vibration. However, if used in an application where they are turned on and off frequently (less than 3 hours per start) the lamp life will be signiﬁcantly shortened. A 100W A-lamp replacement will cost about $5 and will pay you back about $50 - $100 in energy savings over its lifetime!
While this replacement option is generally being written off by consumers as too expensive, it is an incredibly hot
item in the speciﬁcation market. LED is currently about 85% more efﬁcient than incandescent (and its efﬁcacy is still
improving because the technology is still young) and lasts about ﬁfty times as long. Unlike ﬂuorescents, they do provide instant-on light. They can be partially dimmable, typically down to 10% with the proper equipment coordination, The color rendering (CRI) is often similar to ﬂuorescent - but look for a CFL lamp with a CRI over 90 for very good color rendering. LED lamps require a driver, which is similar to a ballast. They are mercury free, and unlike all of the other lamps, they are virtually UV and IR free, so they will not fade fabrics or art. They are sensitive to high temperatures, but they love cold weather. Heat is their enemy, and the astute designer will look for good heat-sinking to ensure that LED junction temperature is maintained at its ideal level. They are not particularly sensitive to vibration. Some look yellow when they are not in use. Others are available in a more traditional looking white color. An A-lamp replacement will cost about $25 - $40 and will pay you back about $240 in energy savings over its lifetime!
This is an exciting time in the lighting industry, with the pace of change increasing exponentially! How can you possibly keep up with it all? My recommendation is to hire a lighting designer. It is my job to keep up with all of these changes, and it has been my privilege to share them with you! I believe that the importance of having a lighting designer on your projects will continue to increase as the technology changes, because lighting designers dedicate themselves to the art and technology of light, and can help you avoid the pitfalls of selecting the wrong technology or even the wrong version of the right technology.
Lisa J. Reed, lighting designer and Principal at Envision Lighting Design, LLC